˘ ˇ - package testing, vibration testing, drop testing ... · penetration , is to be used for...

1

WESTPAK, INC. | 83 Great Oaks Blvd. | San Jose, CA 95119 | Phone (408) 224-1300 | www.westpak.com

10326 Roselle St. | San Diego, CA 92121 | Phone (858) 623-8100

ISO 17028

Accredited

ISO 9001 and 14001

Registered

ISTA

Certified

ASTM F3039 Dye Penetration

Summary and Review

NORA CRIVELLO, VICE PRESIDENT

AUGUST 2014

2



ISO 17028

Accredited

ISO 9001 and 14001

Registered

ISTA

Certified

Introduction

ASTM subcommittee F02.40 has released a new standard to complement the package

integrity testing standards already in use. The new standard, ASTM F3039 Standard Test

Method for Detecting Leaks in Nonporous Packaging or Flexible Barrier Materials by Dye

Penetration, is to be used for detection of edge seal channel leaks through a nonporous

package equal to or greater than 50µm (0.002in). While the traditional ASTM F1929 Dye

Penetration standard is used for porous packaging material, the ASTM F3039 is intended for

nonporous packages – both transparent pouches such as nylon-nylon and opaque (foil-foil)

packages.

While the standard does not forbid testing on lidded trays, there are very few trays that do

not use Tyvek®, and therefore this standard would not apply. Standard ASTM F3039 was

released to expand the package integrity test offerings, not to replace or augment the F1929

or F2096 (bubble emission) standard.

Purpose

The purpose of this standard is to detect channel leaks through the seals of a flexible barrier.

A channel leak can be thought of as a tunnel that runs through the two layers of material

being sealed together. The presence of a channel exposes the package to a potential breach

of integrity as microbes may enter the package where the sterile device is housed.

Throughout the testing and packaging community, there is no agreement concerning the size

of a channel that would be deleterious to the product, and therefore the potential patient.

This test does not measure the size of any channel leak found and is qualitative only.

Therefore, the results of the F3039 testing standard are ‘go/ no-go’.

How the test is run

The F3039 standard calls for dye penetrant to be injected into the package in a volume

relative to the longest edge of the pouch or tray. The seals of transparent packages (poly-

poly or nylon-nylon for example) are visually examined for entrance of dye penetrant into

the seal area. Opaque packages where the dye penetrant is not visible undergo a blotting of

the external edges onto absorbent material. The presence of dye on the exterior of the

3



ISO 17028

Accredited

ISO 9001 and 14001

Registered

ISTA

Certified

package signals a breach of the seal and must be examined more closely. The dye penetrant

will likely come into contact with the product if the seal is breached, and therefore,

functional product testing cannot be conducted on these samples.

How does it work?

The basis of this test methodology lies in an understanding of surface tension. In chemistry,

you likely learned that similar molecules form cohesive bonds with each other. At the

surface of water, the H2O molecules have fewer bonding options since half of the potential

bonds are air molecules. This results in stronger cohesive bonds between the water

molecules at the surface, which we also refer to as surface tension. Surface tension is

measured in dynes/cm with distilled water at ambient conditions coming in at 72.8

dynes/cm1. By comparison, surface tension of mercury is 428 dynes/cm while ethyl alcohol

is 22.3 dynes/cm. It is through manipulation of the surface tension that dye penetration

testing becomes useful.

Two chemicals are added to distilled water to produce the dye penetrant: a surfactant and

dye indicator. Surfactants are chemicals that reduce the surface tension of water.

Surfactants are used in cleaning or degreasing applications as they allow for a lower surface

tension and greater ability for cleaning agent to reach the dirt2. Surfactants are typically

amphiphilic, meaning they are both hydrophobic and hydrophilic (water fearing and water

loving, respectively). Triton-X100 used in dye penetration testing is a non-ionic surfactant

with both a hydrophilic polyethylene oxide chain as well as a hydrocarbon lipophilic group. If

you geek out on this stuff as I do, you’ll be impressed at its proper name: 4-(1,1,3,3-

Tetramethylbutyl)phenyl-polyethylene glycol, t-Octylphenoxypolyethoxyethanol3. Triton X-

100’s purpose is to increase the hydrophilic aspect, thus reducing the surface tension of

water.

1 www.hyperphysics.phy-ast.gsu

2 www.eco-forumn.dk/detergents

3 Sigma Aldrich

4 www.lookchem.com

4



ISO 17028

Accredited

ISO 9001 and 14001

Registered

ISTA

Certified

The second additive is toluidine blue which is

a basic indicator dye. (Remember all those

slides of blue cells from high school biology?

That was likely toluidine blue you were

looking at). Toludine blue is a harmless

substance, but will permanently stain any

clothing it comes into contact with.

What happens then?

When unlike molecules interact, it causes adhesive forces to attract. These bonds are

stronger than those caused by the covalent bonds of like-water molecules. The resulting

effect is seen by water “pulling” away from other water and migrating toward the unlike

surface. You see this effect through the capillary action of absorbent paper towels. The

surface tension of the dye penetrant is typically lower than the surface energy of the

materials generally used for flexible packaging. For example, a foil-foil pouch will have a

surface free energy of around 41.2 dynes/cm while a nylon pouch comes in at 44.3

dynes/cm. Both are higher than the dye penetrant’s surface tension of 25 dynes/cm. The

effect is that when the dye penetrant finds a channel, the surfactant will pull the liquid

through the channel.

Footnote 4

5



ISO 17028

Accredited

ISO 9001 and 14001

Registered

ISTA

Certified

Okay, now what?

If you are currently using the F1929 standard, you may be asking if you should switch to the

F3039 standard to conduct your dye penetration testing. The first question to ask is “Does a

porous material compose part of my package?” If the answer is “yes,” continue with ASTM

F1929 as it is specific to porous packages. However, if you have a nonporous material,

consider switching to F3039. Round-robin studies were conducted on both standards with

comparable results of 0.3% false positives noted.

Conclusion

In conclusion, the ASTM F3039 is a new consensus test standard which provides a means to

test pouches and trays for channel leaks as small as 50µm when nonporous packaging

material is utilized.

Westpak, Inc., an independent testing laboratory accredited to ISO 17025 by A2LA, has

conducted a validation test of this standard and is happy to answer any questions you may

have.

˘ ˇ - package testing, vibration testing, drop testing ... · penetration , is to be used for...

Documents